Modifying emptyset.h and sexpr. Adding SetLanguage.

- Modifies expr/emptyset.h to use SetType only as an incomplete type within expr/emptyset.h. This breaks the include cycle between expr/emptyset.h, expr/expr.h and expr/type.h.
- Refactors SExpr to avoid a potentially infinite cycle. This is likely overkill, but it works.
- Moving Expr::setlanguage and related utilities out of the Expr class and into their own file. This allows files in util/ to know the output language set on an ostream.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/printer/smt2/smt2_printer.cpp b/src/printer/smt2/smt2_printer.cpp
index f93857796..ece4e9177 100644
--- a/src/printer/smt2/smt2_printer.cpp
+++ b/src/printer/smt2/smt2_printer.cpp
@@ -977,7 +977,7 @@ void Smt2Printer::toStream(std::ostream& out, const Command* c,
 static std::string quoteSymbol(TNode n) {
 #warning "check the old implementation. It seems off."
   std::stringstream ss;
-  ss << Expr::setlanguage(language::output::LANG_SMTLIB_V2_5);
+  ss << language::SetLanguage(language::output::LANG_SMTLIB_V2_5);
   return CVC4::quoteSymbol(ss.str());
 }